The invention generally relates to wound dressings. More particularly, the invention relates to vacuum dressings for medical device insertion sites.
Transcutaneous medical devices are catheters, pins, implants and the like which pass through the skin and are indwelling for some variable periods of time. Exemplary of transcutaneous medical devices are central venous catheters, peripheral venous catheters, Swan-Ganz pulmonary catheters, central nervous system implants (ex. external ventricular drainage and ventricular reservoirs), peritoneal dialysis catheters, such as for continuous ambulatory peritoneal dialysis and continuous cyclic peritoneal dialysis, hemodialysis catheters, transvenous pacemaker leads, chest drainage tubes and catheters as well as other cavity drainage tubes and temporary orthopedic pins. All of these transcutaneous medical devices, when in place, have a portion of the device which is external, that is which is left protruding from the skin, and which can be the cause of infection.
The risk of acquiring infections from transcutaneous infections is very high. For instance, the risk of acquiring catheter-related bloodstream infection ranges from 0.9 to 8%. These nosocomial bloodstream infections cause a case fatality of more than 20%, and account for an increase of thousands of dollars in hospital costs per infection, or tens of thousands of dollars per survivor in ICU needing an extra week of hospital stay. As for peritoneal dialysis, a very experienced center today still has a peritonitis rate of one episode per 15 to 25 patient months. The major sources of bacteria in these infections are from surrounding skin.
To prevent infections associated with transcutaneous medical devices, universal precautions such as the use of gloves, mask and a cap in combination with the use of antiseptic preparation at the insertion sites, including the initial application of topical anti-microbial solutions such as alcohol, iodine or more recently chlorexedine is known. A further topical ointment after insertion of the device, such as an ointment containing neomycin, polymyxin and bacitracin, has been shown to prevent catheter colonization/infection, but it may increase the risk of fungal infection. Ointments are also inconvenient, requiring multiple replacements. There have also been attempts to attach a cuff to the catheters, with an anti-microbial agent impregnated in the cuff. Efforts to coat the catheters with anti-microbial agents are known. However, none of these efforts has been completely successful in clinical trials. Presently, the most common catheter dressing used in hospitals comprises sterile gauze or polyurethane film, which both have limited infection control properties and are difficult to keep in place particularly in hospitalized patients that are at the highest risk of infection related to these devices.
Current dressings for medical device insertion sites, such as that shown in use in FIG. 1, fail to provide adequate protection to the insertion site, as they require that the medical device be located underneath the dressing. Because of this, any pressure on or movement of the medical device is associated with the dressing not being in contact with the skin, thereby facilitating infections.
The present invention seeks to overcome these problems, as well as others.